Figure 5.

Activation of primary mouse nociceptors by human blood serum

(A) Protocol for stimulating primary mouse sensory neurons with human serum.

(B) Cumulative distributions of positive response amplitudes after stimulation by serum dilutions (as fold dilution, orange), along with meATP (dashed green) and saline (dashed gray), excluding cells sensitive to initial saline.

(C) Dose-response curve of sensory neuron activation by serum as mean ± SEM along with saline (dashed), excluding cells sensitive to initial saline.

(D) Cumulative distributions of amplitudes of serum-dependent responses in capsaicin-sensitive (red), menthol-sensitive (blue), or meATP-sensitive (green) neurons.

(E) Percentage of capsaicin- (red), menthol- (blue), and meATP-sensitive (green) sensory neurons activated by serum (300-fold dilution) as mean ± SEM.

(F) Cumulative distributions of amplitudes of serum-dependent responses after heat inactivation (Heat, red), proteinase K digestion (ProtK, green), or spin column removal of top 12 abundant proteins (Filtered, blue), relative to unmodified serum (black) and saline (gray).

(G) Percentage of sensory neurons activated by unmodified serum (black), heat-inactivated serum (Heat, red), proteinase K-digested serum (ProtK, green), or serum after abundant protein removal (Filtered, blue), with saline activation, as mean ± SEM.

(H) Percentage of live primary mouse sensory neurons activated by serum samples from nine healthy volunteers (300-fold dilution) as mean ± SEM, along with meATP (250 μM, dashed green).